package com.linlin.blog.bloguser.toolkit;import java.net.URL;public class StringUtil {    public static String extractFileName(String urlString) {        try {            URL url = new URL(urlString);            String path = url.getPath();            String[] parts = path.split("/");            return parts[parts.length - 1];        } catch (Exception e) {            e.printStackTrace();            return null;        }    }}